How can I Import Houdini Pyro VDB Cache data to Blender
Moving a pyro vdb (or any vdb for that matter) from Houdini to Blender 2.9, is fairly straightforward if your pyro sim is set up with a convert vdb and file cache sop.
Here is the end of the Houdini node tree for the pyro vdb shown below:

The convert vdb sop instructs houdini to convert your pyro into a vdb sequence(change it to vdb, as it defaults to volume,) it should look like so in the parameters--&gt; , and the file cache will save it to disk at the output. (be sure to change cache to output to .vdb from .bgeo or you may run into problems on export)

Alternatively, (and for a more efficient way)you may  use a Pyro-Post-Process sop in place of the convert vdb sop. This will allow to do the conversion to vdb and tell houdini to save  the vdb as 16 bit float instead of 32 bit (default).

The parameters of the pyro-post-process should look like this:


Inside of Blender, add a volume object in the scene, Shift+A Volume &gt;Import OpenVBD and select your sequence wherever it was saved to. Blender should now read the vdb sequence exported from houdini without any problems.